Hi, My Friend Is Fearful To Go Back To Her

Hi, my friend is fearful to go back to her doctor because she said all they do is do tests and more tests and don't fix her problem. She's told me a little about her symptoms and I think she has a rectal vaginal fistula. She's afraid she's got cancer so she won't go back to the doctor. What do they do for a r/v fistula? Is it a huge surgery? I'd like to be supportive of her and encourage her to get it repaired.